1. Field of the Invention
The present invention relates generally to methods and systems for security identification, and more particularly, to methods and systems for personnel biometric verification.
2. Background of the Invention
Gate security access control has recently been given increased attention as it provides basic safety protection for facilities and individuals who work in the facilities. In a typical gate security system for a large facility, personnel must show their ID cards and/or display authorization tags on their vehicles in order to gain access to the facility. In some cases, where a guard is not located at the gate, personnel can use a data card, such as an electronic data card, to release a gate to gain access to the facility. Once inside the facility, personnel must typically use the data card to open doors to enter into specific secured areas.
One well known type of security access control system is based on radio frequency identification (RFID), which is illustrated in FIG. 1. RFID system 10 comprises three basic elements: an antenna or coil 11, a transceiver 12 (with decoder), and a transponder (i.e., an RFID tag) 13 electronically programmed with unique identification information. Antenna 11 emits radio frequency signals to activate tag 13 and read and write data to it, and functions as a conduit between tag 13 and transceiver 12. Antenna 11 can take on various shapes and sizes. For example, antenna 11 can be built into a door frame to receive tag data from persons or things passing through the door, or mounted on structures such as an interstate toll booth to monitor the traffic passing on a highway. Antenna 11 is often packaged with transceiver 12 and decoder (not shown) to function as a reader (or interrogator), which can be configured either as a handheld or a fixed-mount device. The reader emits radio waves in a range of one inch to 100 feet or more, thereby establishing a predetermined electromagnetic zone. When an RFID tag passes through the electromagnetic zone, it detects the reader's activation signals. The reader then decodes the data encoded in the tag's integrated circuit and the data is passed to a host computer 15 via an RF module 16 for processing. Generally, RFID tags 13 can be either active or passive. Active RFID tags are powered by an internal battery and are typically readable and rewriteable. In a typical read/write RFID system, an active RFID tag delivers a set of instructions to a machine, and the machine then acts upon those instructions. In contrast, passive RFID tags operate without a separate power source and obtain power generated from the reader.
A significant advantage of RFID systems is the non-contact and non-line-of-sight nature of the technology. In operation, when a person or subject carrying an RFID tag passes through a checkpoint, an RFID reader reads and decodes data stored in the RFID tag and sends the decoded data to a computer for processing. RFID tags can be read through a variety of substances such as snow, fog, ice, paint, and other visually and environmentally challenging conditions. RFID tags can also be read under challenging circumstances such as when RFID-tagged vehicles pass points at relatively high speeds.
RFID systems have been used to control facility access through a gate. In such a case, individuals carry an RFID tag (also referred to herein as a “personal tag”) or display an RFID tag in their vehicle (also referred to herein as a “vehicle tag”). A reader composed of an RF transceiver and an antenna is installed at or near the gate so that when the individual and/or the vehicle is close to the gate, the RFID reader reads the data embedded in the RFID tags and sends the data to a computer for verification. If the data from the tag indicate that the individual or the vehicle is permitted entry, the gate will open to allow the individual or vehicle to enter. On the other hand, if the data shows that the individual or vehicle is not permitted entry, the gate will remain closed. In some cases, a guard will stop the vehicle to acquire more information from the individual or driver of the vehicle.
Reliance solely on an RFID system for identification, however, does not provide adequate security. Since the computer only matches the RFID tag with data stored in a database, it is possible that the person who is carrying a valid RFID tag is, in fact, not authorized to gain access. Also an unauthorized person, who by some means, obtains a valid RFID tag, will be granted access. Thus, a more advanced identification system is required.
Biometric verification is now being employed more frequently to verify personnel identification. Such systems typically comprise a database storing personal biometric information, such as facial templates or features, finger prints, hand geometry, iris prints, thermograms, skin colors of personnel, and others, or any combination of these. In a typical face identification imaging biometric system, the system takes an image or an image sequence of a person and then performs a “one-to-many” verification database search against the images stored in the database; this is done using 2D or 3D image processing technology. However, such a one-to-many search is very slow and often unreliable. Furthermore, present biometric verification systems typically require facial verification in a benign lighting and background environment with no relative facial movement. That is, the person who is requesting access must either stay still or move in a prescribed fashion while the system takes his/her image, or the individual must present their fingers or iris in direct contact to a biometric reader. This presentation requires direct contact and increases the overall time needed for completing the biometric verification task.
As higher levels of security and automation are increasingly demanded, an overall security system must be provided to adequately improve a facility's security posture. The security system must minimize negative effects to work efficiency and quality of work life. Due to the disadvantages of excessively long waiting times and unreliable results mentioned above, currently employed Facial Recognition Systems (FRS) and RFID systems cannot yet uniquely satisfy fast and accurate biometric verification requirements. Thus, a method and system that can more efficiently and rapidly identify personnel and/or vehicles is required.